package com.kele.unsafe;

import java.util.*;
import java.util.concurrent.CopyOnWriteArrayList;

/**
 * @author kele
 * @date 2021/10/9 17:42
 * @description
 */
public class ListTest {
    public static void main(String[] args) {

        /**
         * 并发环境下用arrayList会有并发的异常
         * 1.用 Vector List<String> list=new Vector<>();
         * 2.用Collections.synchronizedList(new ArrayList<>());
         * 3.使用new CopyOnWriteArrayList<>();写入时复制
         */
        List<String> list=new CopyOnWriteArrayList<>();

        for (int i = 0; i <10 ; i++) {
            new  Thread(()->{
                list.add(UUID.randomUUID().toString().substring(0,5));
                System.out.println(list );
            },String.valueOf(i)).start();



        }
    }
}
